Artificial nose for robots

Continued inhalation of carbon dioxide (CO2) in too high concentrations reduces the oxygen-carrying capacity of the blood and makes the cells unable to use the oxygen delivered to them. This oxygen deprivation mainly affects the brain and heart, causing serious poisoning, or even death in the most serious cases. Hence, it is important to have an early detection system that can help people at risk or even emergency services to perceive a dangerously large presence of this gas in the air before it produces harmful effects on health. .

Based on this need, a team of researchers from the Center for Automation and Robotics (CAR) of the Polytechnic University of Madrid (UPM) has managed to develop an artificial nose capable of detecting different gases, including CO2, when they reach critical levels. This innovative device is based on computational fluid dynamics analysis and uses a modular artificial nose, inspired by the inhalation and exhalation process, equipped with an air capture system that works in real time.

“Our work proposes a method to acquire environmental gases using an artificial nose, a sensory system capable of sampling gas (e.g. CO2) within a surrounding range by emulating the behaviour of a real nose, replicating the inhalation and exhalation phases. This is achieved through a distributed air absorption system and channelling the air in a concentrated manner towards an internal sensor for analysis,” explains Christyan Mario Cruz, UPM researcher and lead author of the study.

The implemented system has had a previous design phase that analyzes the behavior of the particles around it through a computational fluid dynamics (CFD) analysis to improve and maximize the quality of the samples acquired from a given area. The information has been used to create maps of CO2 concentration in the environment.

Finally, the nose was integrated into the operating system of a quadruped robot to maximize environmental coverage, taking advantage of its locomotion capabilities in complex terrain.

Robot on which the new artificial nose has been tested. (Photo: UPM)

“Integrated into a quadruped robot, the system can navigate the environment to collect samples, maximizing coverage and offering a complete perspective of the distribution of gases in the area,” says Antonio Barrientos, from CAR and another co-author of this study. “The robotic platform uses a graphical interface to visualize gas concentration maps in real time. This advance promises to improve the efficiency in the detection of substances in the environment,” the researchers add.

The results obtained by the device are encouraging. The aspiration system showed a substantial improvement in measurement concentration, producing more reliable readings by increasing parts per million (ppm) of CO2 by an average of 61% rather than taking measurements with only the sensor exposed to the environment. “This improvement makes it possible to omit exhaustive exploration phases within the robot’s environment to acquire additional data, speeding up the journey through the environment to a single step.”

A device such as the one developed by UPM researchers can be very useful in supporting emergency services in rescue work when the environment may be contaminated by the presence of gases.

“The system can be applied for early detection of living victims in contaminated scenarios, detecting gases, such as CO2 emitted by the victim that causes an anomaly in measurements during a mission. Another application is pre-inspection in a post-disaster environment, warning human rescuers about dangerous areas with possible concentrations of toxic gases,” conclude the UPM researchers.

Christyan Mario Cruz and his colleagues present the technical details of their robot nose in the academic journal Machines, under the title “A Portable Artificial Robotic Nose for CO2 Concentration Monitoring.” (Source: UPM)